Precooling refrigeration system



March 23, 1937. v L. LEE 2,074,614

PRECOOLING REFRIGERATION SYSTEM Filed Nov. 26, 1934 2 Sheets-Sheet l M l W k /rx I 1 772 Jim. 1

LE 1a March 23, 1937. L. c. LEE

PRECOOLING REFRIGERATION SYSTEM Filed Nov 26, 1934 2 Sheets-Sheet 2 Patented Mar. 23, 1937 UNITED STATE PATENT OFFICE 1 Claim.

This invention relates to an improved means and method for precooling refrigerator cars or the like, and has for one of its principal objects the provision of an improved apparatus to be used with the ordinary refrigerator cars, for example, those employing ice for cooling perishable products such as fresh fruits, vegetables, meat or the like, and which shall more effectively preserve such products.

One of the important objects of this invention is the provision, in connection with a refrigerator car, of means for simply, economically and eniciently removing the warm air or what is technically known as field heat from the car after original packing and replacing same with cold air, and which method employs less ice than that heretofore considered necessary and which method, furthermore, can be used to definitely regulate the humidity of the air in the car.

A still further object of the invention is the provision of means to be used in connection with refrigerator cars whereby all need for opening the side doors of the cars during the precooling operation or during transit is overcome.

The improved method of this invention employs, broadly speaking, three steps, the first being the forcible removal of warm air from the inside of the car through the hatches at the top and the replacement thereof by cooler air drawn in from the bottom through the ice compartments. The next step consists in setting up of an internal circulation in the car until the temperature is reduced to the desired point, and the third operation is the same as the first, the purpose, however, being to draw off the saturated cold. air in the car and replace it with dry cold air. In some cases, the third operation may be eliminated.

Another essential object of the invention is the provision of means for accomplishing the abovedescribed operations through a simple, easily applied, yet eifective apparatus.

Other and further important objects of the invention will be apparent from the disclosures in the accompanying drawings and following specification.

The invention, in a preferred form, is illustrated ure 1, showing the apparatus in use for the first operation and the effects thereof.

Figure 3 is a perspective view of the car with a further portion of the apparatus applied and illustrating the operation thereof. 5

Figure 4 is an enlarged view of a portion of the apparatus shown in Figure 3.

Figure 5 is a top plan view of the fan housing.

Figure 6 is a vertical section of the fan housing illustrated in Figure 5.

'As shown in the drawings:

The reference numeral N] indicates generally a refrigerator car which may be of the usual type having partitions l2 for the storage of ice [4, which partitions are provided with the usual up- 10 per and lower screens It and hatch covers IS in the top of the car.

Heretofore, refrigerator cars of this type have been preliminarily loaded with ice, and the hatch covers then closed, leaving the cooling to proceed as best it may, which caused considerable waste of ice and also loss of perishable products due to the fact that the humid air originally in the car was not removed. The invention also avoids a fault existent in other methods of precooling where it is necessaryto open the side doors at the conclusion of the operation for the purpose of removing the apparatus used, with consequent loss of cold air.

In the operation of the present invention, a housing 20 is placed over each of two diagonally opposed hatch openings, the housing including a fan 22 driven by a motor or the like 24, which can be operated by any suitable means, as, for example, a source of current which can be led in'through wires 26.

This housing 20, as best shown in Figures 5 and 6, is adapted to fit snugly on a suitable plate or support therefor 28 (Figure 1) placed in the hatch opening and which can be readily removed by lifting out. Obviously, any other method of removably supporting the housing and fan in the hatch opening can be employed. The motor 24 of the fan is mounted on suitable brackets or the like 32 which are of a type so as not to interfere with the free circulation of air therearound.

In the first operation of the improved method of this invention, a fan 22 in its housing 20 is inserted in each of two diagonally opposed hatch openings in the top of the car after the same has been iced and filled and with the side doors closed. This is best shown in Figure 1. Here, it will be noted, an L-shaped tube 30 is connected to the lower portion of the fan housing 20 with its open end positioned against the inner face of an upper screen I6.

The fans are then operated in a manner to draw or force warm air out of the car through the hatches and with cool fresh air entering through the drain holes 34 at the bottom of the car, all as shown in Figure 2. The drain holes may be of sufiicient number and size to insure desired results. Warm air is discharged into the open, and the fresh air which enters through the drain holes 34 is cold inasmuch as it passes over the ice adjacent the holes and then the same enters the lower part of the car through the lower screen opening in the compartment wall. Additional air, cooled by contact with the higher levels of the ice, also passes into the car proper through the screen. This operation is continued until the temperature of the air in the car is lowered sufficiently to insure the removal of substantially all of the field heat.

The second step of the operation is illustrated in Figure 3 wherein a tube or pipe 3% is mounted in position over the corresponding flange 38 of the motor housing 20 and the other end of this tube directed downwardly into the oppositely disposed hatch of the car, the hatches being otherwise closed to the outside air. Upon starting the motors, an internal circulation is set up as illustrated in Figure 3, the air from the top of the car which is easily warmed being forced upwardly through the tubes 36 and thence downwardly as shown by the arrows over the ice in the ice compartments and outwardly through the lower screen openings and into the bottom of the car, after which it again rises, and this internal circulation is kept up until the temperature inside the car is reduced to the desired point. The fans with their housings can be lifted from one hatch to another or may be simply reversed in the openings if it is desired to change the location of the upwardly and downwardly flowing currents of air in the car. The reversal of the fan operation is best for the purpose of forcing the confined air in the car down over the ice and around through the car.

In the third operation, the equipment is used as shown in Figures 1 and 2 wherein the cold air in the car, which has now been filled to saturation with moisture, and is, therefore, quite humid, is drawn off and replaced with dry cold air, which enters through the drain hole 34 at the bottom of the car and passes over the ice l4 in entermg.

It has been found that this method saves approximately fifty per cent of the ice originally placed in the compartments at the beginning of the precooling operation as other methods consume practically all of the ice originally placed in the car in the first cooling stage. As there is often a delay of several hours after precooling and loading, and before the ice compartments can be replenished and the car started on its journey, this method is considerably superior in preserving the car contents intact. The method also requires much less replenishment of ice during transit as the dryness of the cold air in the car after the operation of the process reduces mold and decay to a considerable extent. The manner of exhausting the warm air from above takes advantage of the natural inclination of warm air to rise and insures a quicker and more satisfactory operation.

I am aware that many changes may be made, and numerous details of construction varied throughout a wide range without departing from the spirit of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than as necessitated by the prior art.

I claim as my invention:

In a refrigerator car having ice compartments, ice hatchways and drain openings, means for drawing outside air into the car through the drain openings at the bottom of the ice compartments and expelling the warm air from said car, said means comprising a removable fan mounted in one of the ice hatchways, and a tube associated with the fan for removing warm humid air through said hatchway, but preventing loss of any cooled air which has contacted the ice in the compartment, said tubes leading over the ice and opening into the upper portion of the car, thereby setting up a circulation of air in the car and over the ice and over the other contents of the car.

LAEL CHARLES LEE. 

